Does PF firewall have stateless rules

[fbsd_user]

Does the OpenBSD Packet Filter firewall have stateless rules?
Meaning, if  I coded a rule to pass in for port 23 without any of the
different state options coded,
do I also have to code the same kind of rule to allow that port 23 packet
back out like in IPFW.

Or is there no stateless rules in PF?
Meaning that coding a rule to pass in for port 23 without any of the
different state options coded,
it defaults to standard state processing and the resulting outbound packet
will be allowed out
because it belongs to the same session.